FOLOWRD borehole deformation gage measure the diametric deformation of a small diameter borehole as it is removed from the surrounding stress field by coaxially coring a large diameter hole.

  • Folowrd borehole deformation gage is designed to measure diametric deformation during over coring along three diameters, 60° apart with 1µɛ resolution
  • Strain and probe temperature indicator and recorders
  • Orientation and placement tool
  • Calibration device
  • Folowrd biaxial chamber

Deformation measurement of in situ stresses is important on the design and control as well as back analyzes of underground opening such as cavern, mines, tunnels, shaft, etc.

It is also useful for determining the inherent stability of pit slopes, foundation excavation, mine pillar, dam abutment and trenches.

Technical Specification

Borehole Diameter 38 mm (EX)
Resolution 1µɛ
Temp Range -5up to +60°C
Overcore Diameter 152 mm (6inch)